1. Field of the Invention
The present invention relates to a method for operating a lock comprising an electronic key and a corresponding reader, and also, to an apparatus employing such a method.
2. Description of the Related Art
Securing items and premises by means of locks operated by keys is standard practice. However, a common security threat is that the system is compromised by losing or copying the key. Such a threat applies equally to traditional mechanical keys as well as to more sophisticated systems employing codes, for example, computer passwords, i.e., should the key or password be copied (or stolen), then the security of the system is compromised. For mechanical locks, this can be costly, e.g., necessitating changing the lock in order to restore security. Recovery can be further exacerbated if the key/password is a xe2x80x98masterxe2x80x99 capable of higher level access.
Concerning electronic keys, to counter the threat of copying, the key may be partitioned into two parts: one associated with the user, the other with a physical key carrier, for example, a user PIN code and associated ATM bankcard. Loss of either (but not both) does not compromise the security of the system. One problem of such 2-part keys lies in the user part: the PIN may be forgotten, so the PIN has to be short to be capable of being memorizedxe2x80x94this means it has a limited number of combinations, possibly allowing a xe2x80x98head-onxe2x80x99 attack where all combinations can be tried in order to gain access. Where the user is allowed to select a code or password, forgetful (or lazy) users may select easy to remember codesxe2x80x94for example, a PIN code xe2x80x981111xe2x80x99, or a password set to be the name of the user""s pet; such codes are inherently insecure.
A further limitation with the keys and codes described above is that they are static. Codes which change are more secure since a lost or stolen code then only has a limited lifetime. A disadvantage is that the code change must be coordinated with the key reader which operates the lock. A further problem is that a code which changes must have many combinations to be sufficiently secure; this implies the use of long codesxe2x80x94this, in turn, may delay system operation for a legitimate user by slowing down the transfer of the keycode to the reader, for example, where the keycode is transferred to the reader by means of a serial communications protocol.
A further problem is that security is weakened where the keycode is accessible to an unauthorized user when being transferred between the key and the reader: for example, eavesdropping the communication of the keycode between the key and the reader that can occur with radio transmitter keys.
In addition, it is useful for system administration purposes that a user may inspect a key to ascertain if it is functioning and perhaps to report status information indicated thereon.
It is, accordingly, an object of the present invention to overcome these and other problems by use of an improved apparatus comprising an electronic key and reader.
In accordance with the present invention, there is provided an apparatus for a lock comprising:
a key comprising a first data processor and a display, the first data processor operable to generate a keycode wherein the keycode is adapted in relation to the operation of the key, to convert the keycode to an image representing the keycode, and to render the image on the display, the display being arranged so that the image is visible on a surface of the key; and
a reader comprising a second data processor, a store and an optical scanner, the optical scanner operable to scan the image visible on the key and to produce scan data, the second data processor operable to receive the scan data, to convert the scan data to a scanned keycode, to compare the scanned keycode with a plurality of keycodes held in the store and to control a lock mechanism in accordance with the result of the comparison.
The key and reader apparatus may be intended to act as an access controller for a lock. As such, the key reader may be situated remotely from the lock with which it is associated. Alternatively, the reader may be integrated into the lock itself or even a product, for example, the reader may be built into a personal computer in which the reader outputs a signal to control the operation of the personal computer in accordance with a keycode comparison. The key function may be integrated within a host product or may be a dedicated unit. The reader may interact with the key for configuration and/or identification purposes. The reader may be enabled by a user authentication procedure. The reader may incorporate a cavity to physically accommodate the unit containing the key thereby facilitating interaction with the key; access to the cavity may be physically controlled by a user authentication procedure.
Also, in accordance with the present invention, there is provided a method for operating a lock wherein a key is read by a reader, the method being supported by a keycode being adapted in relation to the operation of the key, the keycode is converted to an image representing the keycode, the image is arranged to be visible on a surface of the key, wherein the reader optically scans the image to produce scan data, the scan data is converted to a scanned keycode, the scanned keycode is compared with a plurality of keycodes and a lock mechanism is controlled in accordance with the result of the comparison.
The key may display information relevant to the usage of the key, for example, context information. The display may be a liquid crystal display (LCD). A portion of the display may include a keycode, that is, a code which represents an access code for the lock. The keycode may be represented in a variety of formats displayable on the key, both human and/or machine readable.
Alternatively, display of the keycode may be suppressed until such time as the key is scanned by the reader. The keycode may adapt during the period of usage of the key; such adaptation may be invoked due to interaction with the reader and/or the passage of time.